The Magic Jack A921 VoIP USB Phone Adapter Internet Calling Dongle w/ Adapter. Item is in good used condition with some light wear. View pictures. Thisis a sleek silver unit that allows you to make and receive calls using your computer's USB interface. With a single phone line and easy plug-in cord, this adapter from Magic-Jack is a convenient and efficient solution for staying connected at home. The A921 model is designed for seamless integration into your home network setup, providing a reliable and user-friendly option for VoIP communication.